What would Judaism mean on anoth­er planet?

In my short sto­ry ​“What Lights We Have,” (a spin-off from my new nov­el How to Mars) the char­ac­ters are try­ing to fig­ure out how to cel­e­brate the very old hol­i­day of Hanukkah on the plan­et Mars.

They run into all sorts of prob­lems. Mars’ low­er grav­i­ty means that the already-soul-crush­ing­ly tedious game of drei­del (don’t act like you don’t know what I’m talk­ing about) lasts much longer than it would on Earth; they lack the ingre­di­ents for prop­er latkes; they don’t have can­dles. Even when they dis­cov­er a meno­rah app that they can use on their tablets, they’re not sure what to do next. Jew­ish tra­di­tion says to put the lights in a win­dow so that oth­ers out­side your home can see your meno­rah — but these folks are alone on Mars. There’s nobody out­side the habi­ta­tion dome to see the flames.

Then there’s the mat­ter of the cal­en­dar. Judaism has hol­i­days, prayers, and cus­toms that are bound to par­tic­u­lar (Earth) sea­sons or moments in the year. We’re so inter­est­ed in the cal­en­dar that we have a total of four dif­fer­ent New Year’s Days! When you start think­ing about oth­er plan­ets, your ideas about time have to change. If you’re going to do Hanukkah, do you do it once per Mars year, in the Mars win­ter? That would mean wait­ing almost sev­en hun­dred days between one fes­ti­val of lights and the next. Or do you keep your­self tied to Earth and end up doing Hanukkah once per Earth year, which means just about twice dur­ing every Mars year, and so not always dur­ing the dark­est sea­son locally?

And what about Passover, which we’re sup­posed to observe in the spring? Does that mean Earth spring or Mars spring? For what it’s worth, Mars’ spring isn’t quite the ver­dant expe­ri­ence we’re used to here at home — and, if you think Tu B’Shevat, our new year of the trees, feels odd in chilly Feb­ru­ary on the Unit­ed States’ East Coast, wait until you see what it’s like on the per­pet­u­al­ly frigid red planet.

Anoth­er ques­tion is the length of hol­i­days; Passover, for exam­ple, is sev­en days in the land of Israel but eight every­where else, a cus­tom that derives from the dif­fi­cul­ty the priests of Jerusalem had in reach­ing far-flung com­mu­ni­ties to tell them to start cel­e­brat­ing. Well, a place like Mars is pret­ty far-flung. Would Passover need to be nine days there? Or a hun­dred and nine?

Final­ly, we face a ques­tion of place. Although Jews live all around the world these days, the reli­gion still orbits around Israel to a con­sid­er­able extent. Con­gre­ga­tions every­where turn to face in the direc­tion of Jerusalem when recit­ing prayers like the Ami­dah, even if they’re thou­sands of miles away. On Mars, would we need to face the plan­et Earth, in order to keep the focus on Jerusalem?

All this to say: Is Judaism an inex­tri­ca­bly Earth-bound religion?

It’s impor­tant to note that Judaism has already sur­vived a num­ber of enor­mous his­tor­i­cal changes. When the Sec­ond Tem­ple was destroyed by the Romans in 70 CE, Jews had to make a choice: either (a) stick to a cen­tral­ized vision of Judaism with priests, ani­mal sac­ri­fices, and a sin­gle tem­ple as the only legit­i­mate site of wor­ship, or (b) decen­tral­ize Judaism, shift­ing to rab­bis over priests, prayer over sac­ri­fice, and many legit­i­mate sites of wor­ship — syn­a­gogues, com­mu­ni­ty cen­ters, the home — rather than just one. If we hadn’t cho­sen (b), the reli­gion, in the absence of the Tem­ple, would have died. But we adapt­ed, and here we are.

If we want to make our way into out­er space, Judaism is going to have to trans­form still further.

That may already be hap­pen­ing; you could argue that Mars would just be the next step in an expan­sion that start­ed a long time ago. After all, the Jews of Buenos Aires, Syd­ney, and Johan­nes­burg cel­e­brate Hanukkah in sum­mer each year, and Passover in autumn. If some­one want­ed to cel­e­brate Tu B’Shevat in a desert or in Antarc­ti­ca or some­where else on Earth with­out the pos­si­bil­i­ty of trees, nobody would object.

Judaism has been changed by the Earth­ly dias­po­ra. Passover’s dietary laws, for exam­ple, have expand­ed to encom­pass species of grain from con­ti­nents that our Israelite ances­tors nev­er knew. And rab­bis have thought through the logis­tics of cel­e­brat­ing hol­i­days in Ice­land, where nights can get very long or short depend­ing on the time of year — and Shab­bat starts at dif­fer­ent times depend­ing on where you live. So we’re used to deal­ing with new geography.

We may also be becom­ing even more decen­tral­ized with time. As one case in point, some com­mu­ni­ties out­side the land of Israel no longer observe the extra eighth day for fes­ti­vals.

Thus there real­ly isn’t a ques­tion of whether Judaism can be lib­er­at­ed from cer­tain local con­ven­tions of time and place; it’s already hap­pen­ing on a plan­e­tary scale. The next step would just be to extend this adap­ta­tion to the rest of the solar sys­tem, and beyond.

The key is that this evo­lu­tion is not just a leav­ing behind; it’s also a car­ry­ing for­ward. Hanukkah in Reyk­javik is still our Fes­ti­val of Lights; Passover in Mum­bai is the much-loved cel­e­bra­tion of our Lib­er­a­tion; Shab­bat in Christchurch is our day of rest. We change and adapt not to lose some­thing but in order to pre­serve what mat­ters, under new cir­cum­stances, and keep growing.

As the nar­ra­tor of my sto­ry ​“What Lights We Have” says, ​“Jen­ny and I head back to the com­mon room, hand in hand. We end up in front of the vir­tu­al meno­rah, which has stopped flick­er­ing — the dig­i­tal can­dles on this app burn all the way down and then stop, like the real thing. And I feel the same tiny sense of loss that I always have when the can­dles are done. It’s not like this is even the dark­est time of the Mar­t­ian year. But it’s full night now, and in some ways this plan­et is always dark­er than Earth. Maybe those can­dles are what this whole thing is about for me — the some­thing that hap­pens to me when can­dles get lit, and the some­thing that hap­pens to me when they burn out.

“And we go put on the suits — we have radios in our hel­mets in case Eve wakes up and needs us — and head off a few steps into the very dark Mar­t­ian night. We sit under a night sky that is in fact very sim­i­lar to the one we had back on Earth. The con­stel­la­tions are the same. Jen­ny says that’s because the oth­er stars are so far away that Earth and Mars are basi­cal­ly in the same place, as far as the rest of the uni­verse is con­cerned. Which means that a jour­ney like ours has in some sense been too short to have left all that much behind.”